307660 2026-02-12 01:53:21 -0800 Anchor Position ignores transformed parent position 2026-04-24 15:14:28 -0700 1 1 1 Unclassified WebKit Layout and Rendering Safari 26 Mac (Apple Silicon) macOS 26 RESOLVED DUPLICATE 313104 InRadar P2 Normal --- 291856 1 hello kiet.ho bfulgham fantasai.bugs kiet.ho koivisto simon.fraser webkit-bug-importer zalan oldest_to_newest 2180705 0 478325 hello 2026-02-12 01:53:21 -0800 Created attachment 478325 A code example of how anchored items position themselves with differently positioned parents If an anchored item lives inside a transformed parent, the anchored item will ignore the transform and place itself where the item it was anchoring to would have appeared without the transform. This happens in the initial release of Anchor Positioning in WebKit has well as the latest 21623.2.7.11.6 2183001 1 webkit-bug-importer 2026-02-19 01:54:10 -0800 <rdar://problem/170707849> 2204284 2 kiet.ho 2026-04-24 15:14:22 -0700 Hello, thank you for the report and repro. This bug is due to WebKit not implementing support for transformed anchor. We're currently implementing it as we speak, and I can confirm the repro will work with the patch in bug 313104. *** This bug has been marked as a duplicate of bug 313104 *** 478325 2026-02-12 01:53:21 -0800 2026-02-12 01:53:21 -0800 A code example of how anchored items position themselves with differently positioned parents transform-anchor.html text/html 1338 hello PGh0bWw+Cgk8aGVhZD4KCQk8c3R5bGU+CQkKCQkJdWwgewoJCQkJcG9zaXRpb24tYXJlYTogYmxv Y2stZW5kIHNwYW4taW5saW5lLWVuZDsKCQkJCXBvc2l0aW9uLXRyeTogZmxpcC1ibG9jazsKCQkJ CXBvc2l0aW9uOiBhYnNvbHV0ZTsKCQkJfQoJCQkKCQkJI3JlbGF0aXZlIHsKCQkJCWJvcmRlcjog MXB4IHNvbGlkIHJlZDsKCQkJCXdpZHRoOiAyMDBweDsKCQkJCWhlaWdodDogMTAwJTsKCQkJfQoJ CQkKCQkJI2Fic29sdXRlIHsKCQkJCWJvcmRlcjogMXB4IHNvbGlkIGdyZWVuOwoJCQkJd2lkdGg6 IDIwMHB4OwoJCQkJaGVpZ2h0OiAxMDAlOwoJCQkJcG9zaXRpb246IGFic29sdXRlOwoJCQkJdG9w OiAwcHg7CgkJCQlsZWZ0OiAzMDBweDsKCQkJfQoJCQkKCQkJI3RyYW5zbGF0ZSB7CgkJCQlib3Jk ZXI6IDFweCBzb2xpZCBibHVlOwoJCQkJd2lkdGg6IDIwMHB4OwoJCQkJaGVpZ2h0OiAxMDAlOwoJ CQkJcG9zaXRpb246IGFic29sdXRlOwoJCQkJdG9wOiAwcHg7CgkJCQlsZWZ0OiAwcHg7CgkJCQl0 cmFuc2xhdGU6IDYwMHB4IDBweDsKCQkJfQoJCTwvc3R5bGU+Cgk8L2hlYWQ+Cgk8Ym9keT4KCQk8 ZGl2IGlkPSJyZWxhdGl2ZSI+CgkJCTxidXR0b24gcG9wb3ZlcnRhcmdldD0ibWVudTEiIHN0eWxl PSJhbmNob3ItbmFtZTogLS1tZW51MTsiPlJlbGF0aXZlIFBvc2l0aW9uPC9idXR0b24+CgkJCTx1 bCBpZD0ibWVudTEiIHN0eWxlPSJwb3NpdGlvbi1hbmNob3I6IC0tbWVudTE7IiBwb3BvdmVyPgoJ CQkJPGxpPk1lbnUgMTwvbGk+CgkJCQk8bGk+TWVudSAxPC9saT4KCQkJCTxsaT5NZW51IDE8L2xp PgoJCQk8L3VsPgoJCTwvZGl2PgoJCTxkaXYgaWQ9ImFic29sdXRlIj4KCQkJPGJ1dHRvbiBwb3Bv dmVydGFyZ2V0PSJtZW51MiIgc3R5bGU9ImFuY2hvci1uYW1lOiAtLW1lbnUyOyI+QWJzb2x1dGUg UG9zaXRpb248L2J1dHRvbj4KCQkJPHVsIGlkPSJtZW51MiIgc3R5bGU9InBvc2l0aW9uLWFuY2hv cjogLS1tZW51MjsiIHBvcG92ZXI+CgkJCQk8bGk+TWVudSAyPC9saT4KCQkJCTxsaT5NZW51IDI8 L2xpPgoJCQkJPGxpPk1lbnUgMjwvbGk+CgkJCTwvdWw+CgkJPC9kaXY+CgkJPGRpdiBpZD0idHJh bnNsYXRlIj4KCQkJPGJ1dHRvbiBwb3BvdmVydGFyZ2V0PSJtZW51MyIgc3R5bGU9ImFuY2hvci1u YW1lOiAtLW1lbnUzOyI+VHJhbnNsYXRlIFBvc2l0aW9uPC9idXR0b24+CgkJCTx1bCBpZD0ibWVu dTMiIHN0eWxlPSJwb3NpdGlvbi1hbmNob3I6IC0tbWVudTM7IiBwb3BvdmVyPgoJCQkJPGxpPk1l bnUgMzwvbGk+CgkJCQk8bGk+TWVudSAzPC9saT4KCQkJCTxsaT5NZW51IDM8L2xpPgoJCQk8L3Vs PgoJCTwvZGl2PgoJPC9ib2R5Pgo8L2h0bWw+